Contact Dermatitis: Types, Symptoms, Treatment

What is contact dermatitis? 

Contact dermatitis is dermatitis resulting from contact between the skin and a substance that is causing irritation. This particular substance can be an allergen – which is a substance that stirs up an allergic reaction, or an irritant – a substance that harms the skin.

Around 80 percent of cases of contact dermatitis are caused by irritants. There are two types of contact dermatitis:

• Irritant contact dermatitis: Caused by direct damage to the skin from an irritating substance, such as detergents, acids, or solvents. Symptoms can appear within minutes to hours after exposure.
• Allergic contact dermatitis: Occurs when the skin has an allergic reaction to a substance, such as poison ivy, nickel, or certain cosmetics. Symptoms may take 24 to 48 hours to develop after exposure.

If you have atopic eczema, which is the most common form of eczema, you are at a higher risk of developing irritant contact dermatitis.

What are the causes of contact dermatitis?

Contact dermatitis can be caused by:

• An irritant: A substance that directly harms the outer layer of skin.
• An allergen: A substance that causes the immune system to react.

Allergens that may cause contact dermatitis include:

• Cosmetic ingredients: Preservatives, fragrances, hair dye, and nail varnish hardeners.
• Metals: Nickel or cobalt in jewellery.
• Certain topical medicines: Medicines applied right on the skin, such as topical corticosteroids, in rare cases.
• Rubber: This includes latex, which is a kind of naturally occurring rubber.
• Textiles: Specifically, the dyes and resins that are contained in them.
• Strong glues: Epoxy resin adhesives.
• Some plants: Chrysanthemums, sunflowers, daffodils, tulips, and primula.

Common irritants that may cause contact dermatitis include:

• Soaps and detergents
• Antiseptics and antibacterials
• Perfumes and preservatives in toiletries or cosmetics
• Solvents
• Oils used in machines
• Disinfectants
• Acids and alkalis
• Cement
• Powders, dust, and soil
• Water, specifically hard, chalky water or heavily chlorinated water

If you are experiencing the symptoms of irritant contact dermatitis, symptoms can further worsen when exposed to heat, cold, friction (rubbing against the irritant), and low humidity (dry air).

If you have continuous long-term exposure to damaging chemicals or allergens, you may gradually develop symptoms of chronic contact dermatitis, which can persist for many years.

What are the symptoms of contact dermatitis? 

The symptoms can vary in intensity and appearance depending on the substance involved, the duration of exposure, and individual sensitivity. Common symptoms of contact dermatitis include:

• Redness: The affected skin often becomes red and inflamed.
• Itching: A significant symptom is intense itching, which can lead to further irritation from scratching.
• Rash: The appearance of a rash is common, which can be red, swollen, and blistered.
• Dry, cracked, or scaly skin: Chronic contact dermatitis may cause the skin to become dry, cracked, and scaly.
• Blisters: Small, fluid-filled blisters may develop, which can break and form crusts.
• Swelling: The affected area may become swollen.
• Burning or stinging sensation: The skin might feel as though it is burning or stinging.
• Tenderness or pain: The affected area can become sore and painful to touch.

How is contact dermatitis diagnosed?

Diagnosing contact dermatitis involves a combination of patient history, physical examination, and sometimes specific tests to identify the cause.

For suspected allergic contact dermatitis, patch testing is often performed. Small amounts of common allergens are applied to the skin, usually on the back, using adhesive patches. The patches are left in place for 48 hours and then removed, with the skin evaluated at 48 hours and again at 72 to 96 hours for signs of an allergic reaction (e.g., redness, swelling, or small blisters).

Some other tests may also be conducted to rule out other potential causes, including skin lesion biopsy or culture of the skin lesion.

Can contact dermatitis be prevented?

The most effective way to prevent contact dermatitis is to steer clear of the allergens or irritants that lead to your symptoms.

If you are unable to avoid contact, you can take precautions to lower the risk of the allergens or irritants causing symptoms for you, such as:

• If your skin is exposed to an allergen or irritant, wash your skin thoroughly with soap and water as soon as possible. If blisters are broken, use wet and cold compresses to soothe inflammation. Do not scratch the rash, this is to prevent a bacterial infection.
• Protect your hands by wearing gloves. However, do take off your gloves from time to time, as sweating can worsen your symptoms. Wearing cotton gloves underneath rubber gloves may be a useful tip for if rubber irritates your skin.
• Check the ingredients on your make-up or soap to ensure they do not contain any irritants or allergens; sometimes you may need to contact the manufacturer or fact-check online to retrieve specific information. You may need to stop using products that irritate your skin.
• Apply emollients often and in generous amounts. They ensure your skin stays hydrated and also aids in protecting it from allergens and irritants. You could also use emollient soap substitutes instead of normal bar or liquid soaps, which are more likely to cause dry skin.

Make an appointment at Pantai Hospitals

Consult your doctor if your contact dermatitis symptoms worsen or if you notice new symptoms. A dedicated and expert team of dermatologists at Pantai Hospitals is available for consultation to provide the best care and assistance.

Pantai Hospitals has been accredited by the Malaysian Society for Quality in Health (MSQH) for its commitment to patient safety and service quality.